[Piglit] [PATCH] glsl-1.50-execution-primitive-id-no-gs-first-vertex: First provoking vertex variation.

[Roland Scheidegger]

One nitpick otherwise looks good to me.

Reviewed-by: Roland Scheidegger <sroland at vmware.com>

Am 01.12.2014 um 16:57 schrieb jfonseca at vmware.com:
> From: José Fonseca <jfonseca at vmware.com>
> 
> Adapt the primitive-id-no-gs-first test case to first provoking vertex
> convention, exposing a bug in llvmpipe.
> ---
>  tests/shaders/shader_runner.c                      | 15 ++++++
>  .../primitive-id-no-gs-first-vertex.shader_test    | 63 ++++++++++++++++++++++
>  2 files changed, 78 insertions(+)
>  create mode 100644 tests/spec/glsl-1.50/execution/primitive-id-no-gs-first-vertex.shader_test
> 
> diff --git a/tests/shaders/shader_runner.c b/tests/shaders/shader_runner.c
> index 628ef44..fb498fb 100644
> --- a/tests/shaders/shader_runner.c
> +++ b/tests/shaders/shader_runner.c
> @@ -1924,6 +1924,19 @@ set_patch_parameter(const char *line)
>  #endif
>  }
>  
> +void
> +set_provoking_vertex(const char *line)
> +{
> +	if (string_match("first", line)) {
> +		glProvokingVertexEXT(GL_FIRST_VERTEX_CONVENTION_EXT);
> +	} else if (string_match("last", line)) {
> +		glProvokingVertexEXT(GL_LAST_VERTEX_CONVENTION_EXT);
> +	} else {
> +		fprintf(stderr, "Unknown provoking vertex parameter `%s'\n", line);
> +		piglit_report_result(PIGLIT_FAIL);
> +	}
> +}
> +
>  static const struct string_to_enum enable_table[] = {
>  	{ "GL_CLIP_PLANE0", GL_CLIP_PLANE0 },
>  	{ "GL_CLIP_PLANE1", GL_CLIP_PLANE1 },
> @@ -2601,6 +2614,8 @@ piglit_display(void)
>  			set_parameter(line + strlen("parameter "));
>  		} else if (string_match("patch parameter ", line)) {
>  			set_patch_parameter(line + strlen("patch parameter "));
> +		} else if (string_match("provoking vertex ", line)) {
> +			set_provoking_vertex(line + strlen("provoking vertex "));
>  		} else if (string_match("link error", line)) {
>  			link_error_expected = true;
>  			if (link_ok) {
> diff --git a/tests/spec/glsl-1.50/execution/primitive-id-no-gs-first-vertex.shader_test b/tests/spec/glsl-1.50/execution/primitive-id-no-gs-first-vertex.shader_test
> new file mode 100644
> index 0000000..dd97b0f
> --- /dev/null
> +++ b/tests/spec/glsl-1.50/execution/primitive-id-no-gs-first-vertex.shader_test
> @@ -0,0 +1,63 @@
> +# Check proper functioning of the gl_PrimitiveID fragment shader
> +# input, in the case where there is no geometry shader, and provoking vertex
> +# is set to first vertex.
> +
> +[require]
> +GLSL >= 1.50
> +GL_EXT_provoking_vertex
> +
> +[vertex shader]
> +#version 150
> +
> +in vec4 piglit_vertex;
> +flat out int vertex_id;
> +
> +void main()
> +{
> +  gl_Position = piglit_vertex;
> +  vertex_id = gl_VertexID;
> +}
> +
> +[fragment shader]
> +#version 150
> +
> +flat in int vertex_id;
> +
> +void main()
> +{
> +  /* We draw a triangle fan containing 6 vertices, so the relationship between
> +   * the primitive ID and the input vertex ID's should be:
> +   *
> +   * Primitive ID  Vertex ID's  Provoking vertex ID
> +   *  0             0 1 2        1
> +   *  1             0 2 3        2
> +   *  2             0 3 4        3
> +   *  3             0 4 5        4
> +   *
> +   * Since vertex_id uses interpolation qualifier "flat", it should
> +   * always receive the value from the provoking vertex.  Therefore,
> +   * by the table above, it should always be 2 greater than the
should be 1 greater

> +   * expected value of gl_PrimitiveID.
> +   */
> +  int expected_primitive_id = vertex_id - 1;
> +  if (expected_primitive_id == gl_PrimitiveID)
> +    gl_FragColor = vec4(0.0, 1.0, 0.0, 1.0);
> +  else
> +    gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
> +}
> +
> +[vertex data]
> +piglit_vertex/float/2
> +-1.0 -1.0
> +-1.0  1.0
> + 0.0  1.0
> + 1.0  1.0
> + 1.0  0.0
> + 1.0 -1.0
> +
> +[test]
> +clear color 0.0 0.0 0.0 0.0
> +clear
> +provoking vertex first
> +draw arrays GL_TRIANGLE_FAN 0 6
> +probe all rgba 0.0 1.0 0.0 1.0
>